1. Field of the Invention
This invention relates to a light emitting device, more particularly to a light emitting device including a chip-mounting base and a transparent encapsulant bonded to the chip-mounting base through a bonding material of a nitride or oxide compound.
2. Description of the Related Art
FIG. 1 illustrates a conventional light emitting device that includes a cup-shaped base 11 defining a recess, a pair of conductive leads 13 mounted on the base 11, a light emitting chip 12 mounted on the base 11 within the recess and wire-bonded to the conductive leads 13 through a pair of bonding wires 15, and an encapsulant 14 filling the recess and enclosing the light emitting chip 12. The conventional light emitting device is disadvantageous in that it has a relatively poor efficiency in dissipating heat generated by the light emitting chip 12.
U.S. Pat. No. 6,274,924 discloses a light emitting device that uses a metallic material for the base so as to enhance the heat dissipating efficiency. However, the transparent encapsulant tends to peel off from the base due to a relatively large difference in expansion coefficients therebetween.